path: root/arch/x86_64
diff options
authorKeshavamurthy, Anil S <anil.s.keshavamurthy@intel.com>2007-10-21 16:41:57 -0700
committerLinus Torvalds <torvalds@woody.linux-foundation.org>2007-10-22 08:13:19 -0700
commit49a0429e53f29109cbf1eadd89497286ba81f1ae (patch)
treeb44c5131bd12881b32ab46ff92b07f8f1c8e9800 /arch/x86_64
parente820482cd2621dba60e403af1c54502daa54b220 (diff)
Intel IOMMU: Iommu floppy workaround
This config option (DMAR_FLPY_WA) sets up 1:1 mapping for the floppy device so that the floppy device which does not use DMA api's will continue to work. Once the floppy driver starts using DMA api's this config option can be turn off or this patch can be yanked out of kernel at that time. [akpm@linux-foundation.org: cleanups, rename things, build fix] [jengelh@computergmbh.de: Kconfig fixes] Signed-off-by: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com> Cc: Andi Kleen <ak@suse.de> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Muli Ben-Yehuda <muli@il.ibm.com> Cc: "Siddha, Suresh B" <suresh.b.siddha@intel.com> Cc: Arjan van de Ven <arjan@infradead.org> Cc: Ashok Raj <ashok.raj@intel.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Christoph Lameter <clameter@sgi.com> Cc: Greg KH <greg@kroah.com> Signed-off-by: Jan Engelhardt <jengelh@gmx.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'arch/x86_64')
1 files changed, 10 insertions, 0 deletions
diff --git a/arch/x86_64/Kconfig b/arch/x86_64/Kconfig
index 5cf941774347..c2d24991bb2b 100644
--- a/arch/x86_64/Kconfig
+++ b/arch/x86_64/Kconfig
@@ -772,6 +772,16 @@ config DMAR_GFX_WA
all the OS-visible memory. Hence the driver can continue
to use physical addresses for DMA.
+ bool
+ depends on DMAR
+ default y
+ help
+ Floppy disk drivers are know to bypass DMA API calls
+ thereby failing to work when IOMMU is enabled. This
+ workaround will setup a 1:1 mapping for the first
+ 16M to make floppy (an ISA device) work.
source "drivers/pci/pcie/Kconfig"
source "drivers/pci/Kconfig"